Timgad (tĬm´găd), ancient Thamugadi, ruined city, Algeria, S of Constantine. It is sometimes called the Pompeii of North Africa because of the extensive remains of the Roman city founded here by Trajan in AD 100. This city was destroyed by Berbers in the 7th cent. and was unknown until excavations were begun in 1881. Its Roman ruins, which include a triumphal arch, public baths, a theater, a library, and a forum, are the best preserved and most extensive in Africa.